Substituted barbituric acids.



. UNITED STATES PATENT OFFICE.

WILHELM HIEMENZ AND LUDWIG TAUB, OF ELBERFELID, GERMANY, ASSIGNOBS TO SYNTHETIC PATENTS 00., INC., OF NEW YORK, N. Y. A CORPORATION OF NEW YORK. I

SUBSTITUTED B ARIBITURIC ACIDS.

No Drawing.

To all whom it may concern:

Be it known that we, WILHELM HIEMENZ and LUDWIG TAUB, doctors of philosophy, chemists, citizens of the German Empire,

residing at Elberfeld, Germany, have in-' vented new and useful Improvements in (io-a'zn R stands for an alkyl, R for a hydrocarbon radical and R" for an alkylene radical e. g.

CH,, -'CH CH The new products have proved to be valuable hypnotics, an average single dose being from to 1; gram. They are white crystals scarcely soluble in water and forming salts with alkalis. I

The process for their production consists oooc n, N11

Crystallizedfrom alcohol it forms white crystals melting at 185 C. It is scarcely soluble in water. It possesses the property of forming salts with many. metals, e. g. the alkali metals, or calcium, the hydrogen of the NH group being replaced by the metal. It may be either used in the acid or salt form. The sodium salt is a white too'can crystalline powder easily soluble in water.

turic acids of the following general formula CO-NH I ll/ 0 an I wherein R stands for an alkyl, R for a hydrocarbon radical, and R for an alkylene radical, the new substances being white Specification of Letters Patent.

4 Patented nebizv, 1917.

Application filed March 23, 1915; Serial No. 16,422.

in condensing substituted malonic esters havlng most probably the formula:

' coon nos 4 (the R having the above given meaning) with guanidin in the presence of sodium alcoholate, and splitting off the imino group by means of an acid.

In order to illustrate the new process more fully the following example is given the parts being by weight :-308 parts 0 ethylphenoxyethylmalonic acid diethyl ester are boiled during eight hours in a vessel provided with a reflux condenser together with a solution of parts of sodium in absolute alcohol and 140 parts of guanidin nitrate. 4 The resulting iminobarbituric acid is then heated during four hours with a 40 per cent. sul-. furic acid and the resulting barbituric acid is crystallized from alcohol (80 per cent).

The process proceeds most probably in accordance with the following equation': 7

H co-N n d to ZCgHgsOH man.

I cmsocgm 1 ILH crystals scarcely soluble in water, forming soluble salts with alkalis; and being valuable hypnotics, substantially as described.

2. The herein described substituted barbituric acids of the following general formula:

io-5n (lo-iii! wherein R" stands for an alkyl, R for an aryl and R for an alkylene radical, the new substances being white crystals scarcely soluble in water, forming soluble salts with alkalis; and being valuable hypnotics, substantially as described.-

3; The herein described substituted barbituric acids of the following general formula:

co-nn v s an wherein R stands for an alkyl, R for an aryl of the benzene series and R for an ethylene radical, the new substances being white crystals scarcely soluble in water, forming soluble salts with alkalis; and being valuable hypnotics, substantially as described.

4. The herein described ethylphenoxyethylbarbitur ic acid of the following gen- 5 eral formula:

10 being White crystals melting at 185 (1., scarcely soluble in Water, forming soluble salts with alkalis, and being a valuable hypnotic, substantially as described.

In testimony whereof We have hereunto set our hands in the presence of tWo subscribl5 ing Witnesses.

WILHELM HIEMENZ. 11.8. LUDWIG TAUB. [L.s.]

Witnesses HELEN NUFER, ALBERT NU'FER. 

